package com.flong.commons.lang.reflect;
import java.beans.BeanInfo;
import java.beans.IntrospectionException;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.commons.beanutils.PropertyUtils;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.Validate;
import org.apache.log4j.Logger;
import org.springframework.util.Assert;


/**
 * 反射工具类.
 * 提供调用getter/setter方法, 访问私有变量, 调用私有方法, 获取泛型类型Class, 被AOP过的真实类等工具函数.
 * @author liangjilong
 * @version 2013-01-15
 */
@SuppressWarnings("all")
public class Reflections {
	
	private static final String SETTER_PREFIX = "set";

	private static final String GETTER_PREFIX = "get";

	private static final String CGLIB_CLASS_SEPARATOR = "$$";
	
	private static Logger logger = Logger.getLogger(Reflections.class);

	/**
	 * 调用Getter方法.
	 * 支持多级，如：对象名.对象名.方法
	 */
	public static Object invokeGetter(Object obj, String propertyName) {
		Object object = obj;
		for (String name : StringUtils.split(propertyName, ".")){
			String getterMethodName = GETTER_PREFIX + StringUtils.capitalize(name);
			object = invokeMethod(object, getterMethodName, new Class[] {}, new Object[] {});
		}
		return object;
	}

	/**
	 * 调用Setter方法, 仅匹配方法名。
	 * 支持多级，如：对象名.对象名.方法
	 */
	public static void invokeSetter(Object obj, String propertyName, Object value) {
		Object object = obj;
		String[] names = StringUtils.split(propertyName, ".");
		for (int i=0; i<names.length; i++){
			if(i<names.length-1){
				String getterMethodName = GETTER_PREFIX + StringUtils.capitalize(names[i]);
				object = invokeMethod(object, getterMethodName, new Class[] {}, new Object[] {});
			}else{
				String setterMethodName = SETTER_PREFIX + StringUtils.capitalize(names[i]);
				invokeMethodByName(object, setterMethodName, new Object[] { value });
			}
		}
	}

	/**
	 * 直接读取对象属性值, 无视private/protected修饰符, 不经过getter函数.
	 */
	public static Object getFieldValue(final Object obj, final String fieldName) {
		Field field = getAccessibleField(obj, fieldName);

		if (field == null) {
			throw new IllegalArgumentException("Could not find field [" + fieldName + "] on target [" + obj + "]");
		}

		Object result = null;
		try {
			result = field.get(obj);
		} catch (IllegalAccessException e) {
			logger.info("不可能抛出的异常{}"+e.getMessage());
		}
		return result;
	}

	/**
	 * 直接设置对象属性值, 无视private/protected修饰符, 不经过setter函数.
	 */
	public static void setFieldValue(final Object obj, final String fieldName, final Object value) {
		Field field = getAccessibleField(obj, fieldName);

		if (field == null) {
			throw new IllegalArgumentException("Could not find field [" + fieldName + "] on target [" + obj + "]");
		}

		try {
			field.set(obj, value);
		} catch (IllegalAccessException e) {
			logger.error("不可能抛出的异常:{}"+ e.getMessage());
		}
	}

	/**
	 * 直接调用对象方法, 无视private/protected修饰符.
	 * 用于一次性调用的情况，否则应使用getAccessibleMethod()函数获得Method后反复调用.
	 * 同时匹配方法名+参数类型，
	 */
	public static Object invokeMethod(final Object obj, final String methodName, final Class<?>[] parameterTypes,
			final Object[] args) {
		Method method = getAccessibleMethod(obj, methodName, parameterTypes);
		if (method == null) {
			throw new IllegalArgumentException("Could not find method [" + methodName + "] on target [" + obj + "]");
		}

		try {
			return method.invoke(obj, args);
		} catch (Exception e) {
			throw convertReflectionExceptionToUnchecked(e);
		}
	}

	/**
	 * 直接调用对象方法, 无视private/protected修饰符，
	 * 用于一次性调用的情况，否则应使用getAccessibleMethodByName()函数获得Method后反复调用.
	 * 只匹配函数名，如果有多个同名函数调用第一个。
	 */
	public static Object invokeMethodByName(final Object obj, final String methodName, final Object[] args) {
		Method method = getAccessibleMethodByName(obj, methodName);
		if (method == null) {
			throw new IllegalArgumentException("Could not find method [" + methodName + "] on target [" + obj + "]");
		}

		try {
			return method.invoke(obj, args);
		} catch (Exception e) {
			throw convertReflectionExceptionToUnchecked(e);
		}
	}

	/**
	 * 循环向上转型,获取对象的DeclaredField.
	 */
	public static Field getDeclaredField(final Object object,
			final String fieldName) throws NoSuchFieldException {
		Assert.notNull(object);
		return getDeclaredField(object.getClass(), fieldName);
	}

	/**
	 * 循环向上转型,获取类的DeclaredField.
	 */
	public static Field getDeclaredField(final Class clazz, final String fieldName) throws NoSuchFieldException {
		Assert.notNull(clazz);
		Assert.hasText(fieldName);
		for (Class superClass = clazz; superClass != Object.class; superClass = superClass.getSuperclass()) {
			try {
				return superClass.getDeclaredField(fieldName);
			} catch (NoSuchFieldException e) {
				// Field不在当前类定义,继续向上转型
			}
		}
		throw new NoSuchFieldException("No such field: " + clazz.getName()
				+ '.' + fieldName);
	}
	/**
	 * 循环向上转型, 获取对象的DeclaredField, 并强制设置为可访问.
	 * 
	 * 如向上转型到Object仍无法找到, 返回null.
	 */
	public static Field getAccessibleField(final Object obj, final String fieldName) {
		Validate.notNull(obj, "object can't be null");
		Validate.notBlank(fieldName, "fieldName can't be blank");
		for (Class<?> superClass = obj.getClass(); superClass != Object.class; superClass = superClass.getSuperclass()) {
			try {
				Field field = superClass.getDeclaredField(fieldName);
				makeAccessible(field);
				return field;
			} catch (NoSuchFieldException e) {//NOSONAR
				// Field不在当前类定义,继续向上转型
				continue;// new add
			}
		}
		return null;
	}

	/**
	 * 循环向上转型, 获取对象的DeclaredMethod,并强制设置为可访问.
	 * 如向上转型到Object仍无法找到, 返回null.
	 * 匹配函数名+参数类型。
	 * 
	 * 用于方法需要被多次调用的情况. 先使用本函数先取得Method,然后调用Method.invoke(Object obj, Object... args)
	 */
	public static Method getAccessibleMethod(final Object obj, final String methodName,
			final Class<?>... parameterTypes) {
		Validate.notNull(obj, "object can't be null");
		Validate.notBlank(methodName, "methodName can't be blank");

		for (Class<?> searchType = obj.getClass(); searchType != Object.class; searchType = searchType.getSuperclass()) {
			try {
				Method method = searchType.getDeclaredMethod(methodName, parameterTypes);
				makeAccessible(method);
				return method;
			} catch (NoSuchMethodException e) {
				// Method不在当前类定义,继续向上转型
				continue;// new add
			}
		}
		return null;
	}

	/**
	 * 循环向上转型, 获取对象的DeclaredMethod,并强制设置为可访问.
	 * 如向上转型到Object仍无法找到, 返回null.
	 * 只匹配函数名。
	 * 
	 * 用于方法需要被多次调用的情况. 先使用本函数先取得Method,然后调用Method.invoke(Object obj, Object... args)
	 */
	public static Method getAccessibleMethodByName(final Object obj, final String methodName) {
		Validate.notNull(obj, "object can't be null");
		Validate.notBlank(methodName, "methodName can't be blank");

		for (Class<?> searchType = obj.getClass(); searchType != Object.class; searchType = searchType.getSuperclass()) {
			Method[] methods = searchType.getDeclaredMethods();
			for (Method method : methods) {
				if (method.getName().equals(methodName)) {
					makeAccessible(method);
					return method;
				}
			}
		}
		return null;
	}

	/**
	 * 改变private/protected的方法为public，尽量不调用实际改动的语句，避免JDK的SecurityManager抱怨。
	 */
	public static void makeAccessible(Method method) {
		if ((!Modifier.isPublic(method.getModifiers()) || !Modifier.isPublic(method.getDeclaringClass().getModifiers()))
				&& !method.isAccessible()) {
			method.setAccessible(true);
		}
	}

	/**
	 * 改变private/protected的成员变量为public，尽量不调用实际改动的语句，避免JDK的SecurityManager抱怨。
	 */
	public static void makeAccessible(Field field) {
		if ((!Modifier.isPublic(field.getModifiers()) || !Modifier.isPublic(field.getDeclaringClass().getModifiers()) || Modifier
				.isFinal(field.getModifiers())) && !field.isAccessible()) {
			field.setAccessible(true);
		}
	}

	/**
	 * 通过反射, 获得Class定义中声明的泛型参数的类型, 注意泛型必须定义在父类处
	 * 如无法找到, 返回Object.class.
	 * eg.
	 * public UserDao extends HibernateDao<User>
	 *
	 * @param clazz The class to introspect
	 * @return the first generic declaration, or Object.class if cannot be determined
	 */
	
	public static <T> Class<T> getClassGenricType(final Class clazz) {
		return getClassGenricType(clazz, 0);
	}

	/**
	 * 通过反射, 获得Class定义中声明的父类的泛型参数的类型.
	 * 如无法找到, 返回Object.class.
	 * 
	 * 如public UserDao extends HibernateDao<User,Long>
	 *
	 * @param clazz clazz The class to introspect
	 * @param index the Index of the generic ddeclaration,start from 0.
	 * @return the index generic declaration, or Object.class if cannot be determined
	 */
	public static Class getClassGenricType(final Class clazz, final int index) {

		Type genType = clazz.getGenericSuperclass();

		if (!(genType instanceof ParameterizedType)) {
			logger.warn(clazz.getSimpleName() + "'s superclass not ParameterizedType");
			return Object.class;
		}

		Type[] params = ((ParameterizedType) genType).getActualTypeArguments();

		if (index >= params.length || index < 0) {
			logger.warn("Index: " + index + ", Size of " + clazz.getSimpleName() + "'s Parameterized Type: "
					+ params.length);
			return Object.class;
		}
		if (!(params[index] instanceof Class)) {
			logger.warn(clazz.getSimpleName() + " not set the actual class on superclass generic parameter");
			return Object.class;
		}

		return (Class) params[index];
	}
	
	public static Class<?> getUserClass(Object instance) {
		Assert.notNull(instance, "Instance must not be null");
		Class clazz = instance.getClass();
		if (clazz != null && clazz.getName().contains(CGLIB_CLASS_SEPARATOR)) {
			Class<?> superClass = clazz.getSuperclass();
			if (superClass != null && !Object.class.equals(superClass)) {
				return superClass;
			}
		}
		return clazz;

	}
	
	/**
	 * 将反射时的checked exception转换为unchecked exception.
	 */
	public static RuntimeException convertReflectionExceptionToUnchecked(Exception e) {
		if (e instanceof IllegalAccessException || e instanceof IllegalArgumentException
				|| e instanceof NoSuchMethodException) {
			return new IllegalArgumentException(e);
		} else if (e instanceof InvocationTargetException) {
			return new RuntimeException(((InvocationTargetException) e).getTargetException());
		} else if (e instanceof RuntimeException) {
			return (RuntimeException) e;
		}
		return new RuntimeException("Unexpected Checked Exception.", e);
	}

	/**
	 * 提取集合中的对象的属性,组合成List.
	 * 
	 * @param collection
	 *            来源集合.
	 * @param propertityName
	 *            要提取的属性名.
	 */
	
	public static List fetchElementPropertyToList(final Collection collection,
			final String propertyName) throws Exception {

		List list = new ArrayList();

		for (Object obj : collection) {
			list.add(PropertyUtils.getProperty(obj, propertyName));
		}

		return list;
	}

	/**
	 * 提取集合中的对象的属性,组合成由分割符分隔的字符串.
	 * 
	 * @param collection
	 *            来源集合.
	 * @param propertityName
	 *            要提取的属性名.
	 * @param separator
	 *            分隔符.
	 */
	public static String fetchElementPropertyToString(
			final Collection collection, final String propertyName,
			final String separator) throws Exception {
		List list = fetchElementPropertyToList(collection, propertyName);
		return StringUtils.join(list, separator);
	}

	/**
	 * 获取javaBean的属性
	 * @param <T>
	 * 
	 * @param clazz
	 * @return
	 */
	public static <T> List<String> getAllElementProperty(Class<T> clazz) {
		List<String> list = new ArrayList<String>();
		PropertyDescriptor descriptor[] = PropertyUtils
				.getPropertyDescriptors(clazz);
		for (PropertyDescriptor descriptor2 : descriptor) {
			if ("class".equalsIgnoreCase(descriptor2.getName())) {
				continue;
			}
			list.add(descriptor2.getName());
		}
		return list;
	}
	
	
	 /**
	     * 将一个 Map 对象转化为一个 JavaBean
	     * @param clazz 要转化的类型
	     * @param map 包含属性值的 map
	     * @return 转化出来的 JavaBean 对象
	     * @throws IntrospectionException 如果分析类属性失败
	     * @throws IllegalAccessException 如果实例化 JavaBean 失败
	     * @throws InstantiationException 如果实例化 JavaBean 失败
	     * @throws InvocationTargetException 如果调用属性的 setter 方法失败
	     */
	    public static <T> T MapToBean(Class<T> clazz, Map map) {
	        T obj = null;
	        try {
	            BeanInfo beanInfo = Introspector.getBeanInfo(clazz);
	            obj = clazz.newInstance(); // 创建 JavaBean 对象
	 
	            // 给 JavaBean 对象的属性赋值
	            PropertyDescriptor[] propertyDescriptors = beanInfo.getPropertyDescriptors();
	            for (int i = 0; i < propertyDescriptors.length; i++) {
	                PropertyDescriptor descriptor = propertyDescriptors[i];
	                String propertyName = descriptor.getName();
	                if (map.containsKey(propertyName)) {
	                    // 下面一句可以 try 起来，这样当一个属性赋值失败的时候就不会影响其他属性赋值。
	                    Object value = map.get(propertyName);
	                    if ("".equals(value)) {
	                        value = null;
	                    }
	                    Object[] args = new Object[1];
	                    args[0] = value;
	                    try {
	                        descriptor.getWriteMethod().invoke(obj, args);
	                    } catch (InvocationTargetException e) {
	                        System.out.println("字段映射失败");
	                    }
	                }
	            }
	        } catch (IllegalAccessException e) {
	            System.out.println("实例化 JavaBean 失败");
	        } catch (IntrospectionException e) {
	            System.out.println("分析类属性失败");
	        } catch (IllegalArgumentException e) {
	            System.out.println("映射错误");
	        } catch (InstantiationException e) {
	            System.out.println("实例化 JavaBean 失败");
	        }
	        return (T) obj;
	    }
	public static Map toMapOneUpper(Object bean) {
		Class<? extends Object> clazz = bean.getClass();
		Map<Object, Object> returnMap = new HashMap<Object, Object>();
		BeanInfo beanInfo = null;
		try {
			beanInfo = Introspector.getBeanInfo(clazz);
			PropertyDescriptor[] propertyDescriptors = beanInfo.getPropertyDescriptors();
			for (int i = 0; i < propertyDescriptors.length; i++) {
				PropertyDescriptor descriptor = propertyDescriptors[i];
				String propertyName = descriptor.getName();
				if (!propertyName.equals("class")) {
					propertyName = oneNumToUpperCase(propertyName);
					Method readMethod = descriptor.getReadMethod();
					Object result = null;
					result = readMethod.invoke(bean, new Object[0]);
					if (null != propertyName) {
						propertyName = propertyName.toString();
					}
					if (null != result) {
						result = result.toString();
					}
					returnMap.put(propertyName, result);
				}
			}
		} catch (IntrospectionException e) {
			System.out.println("分析类属性失败");
		} catch (IllegalAccessException e) {
			System.out.println("实例化 JavaBean 失败");
		} catch (IllegalArgumentException e) {
			System.out.println("映射错误");
		} catch (InvocationTargetException e) {
			System.out.println("调用属性的 setter 方法失败");
		}
		return returnMap;
	}

	private static String oneNumToUpperCase(String propertyName) {
		char[] charArray = propertyName.toCharArray();
		String numOne = charArray[0] + "";
		char[] chara = numOne.toUpperCase().toCharArray();
		charArray[0] = chara[0];
		return String.valueOf(charArray);

	}
}
